This invention relates to a clutch disc for use in a clutch of an automobile etc.
In conventional clutch as shown in FIG. 5, there has been a clutch disc operating in three successive stages by providing a hub flange 31 with a total of six window holes, each two of first stage window holes 32, second stage window holes 33, and third stage window holes 34. However, since notched portions 36 for stop pins 35 have been arranged completely separately from all the window holes 32, 33, 34, i.e. have not been formed integrally with any one of window holes; portions of a boss flange (hatched portions of FIG. 5) at inner peripheral sides of the notched portions 36 have not been utilized efficiently. Accordingly, peripheral lengths of each window hole 32, 33, 34 have been limited remarkably so that the maximum angle of torsion has not been able to be enlarged more than 8 degrees. In recent years, however, a clutch disc having an angle of torsion of up to approximately 14 degrees has become frequently required depending on types of automobile so that the clutch disc such as illustrated in FIG. 5 has not been able to meet such requirement at all.
An object of this invention is to provide a clutch disc which provides a large maximum angle of torsion and can be easily manufactured.
In order to accomplish the above object, in this invention; in a clutch disc wherein window holes are arranged on a circumference of a hub flange with spaces provided therebetween, resiliently deformable coil springs are fitted in said window holes in the circumferential direction, notched portions having a prescribed length in the circumferential direction, are formed at central portions between window holes on an outer peripheral edge. Stop pins on side plates are adapted to engage with said notched portions with prescribed plays left therebetween in the circumferential direction and a clutch disc is formed with coil receiving notches integrally interconnected with inner peripheral edges of said notched portions, said coil receiving notches are further fitted therein with coil springs, and window holes engaging with the coil springs are provided on said side plates.